interface Pointer2D {
  x: number
  y: number
}

interface Pointer3D extends Pointer2D {
  z: number
}

/* const p: Pointer3D = {
  x: 8,
  y: 14,
  z: 66,
} */

// !如果把对象提取出来，里面的属性在满足类型的基础上可以更多
const o = {
  x: 8,
  y: 14,
  z: 66,
  xxx: 888,
}
const p: Pointer3D = o
export {}
